V/IOS'^'^^'  RESERVE 

/j  ^,  S.  nikWm  of  Agriculture, 


CONNECTICUT 

AGRICULTURAL  EXPERIMLNT  STATION. 

NEW  HAVEN,    CONN. 


s 


-.3 


BXJLLETIlSr     121,     JXJLIT,     1S©5. 


THE  ELM  LEAF  BEETLE. 

THE  SAN  JOSE  SCALE. 


Elm  Leaf  Beetle. — a,  eggs  ;  b,  larvfe  ;  c,  adult ;  e,  eggs,  enlarged ;  /, 
sculpture  of  eggs  ;  g,  larva,  enlarged  ;  h,  side  view  of  greatly  enlarged  seg- 
ment of  larva ;  i,  dorsal  view  of  same  ;  j,  pupa,  enlarged  ;  k,  beetle,  enlarged  : 
I,  portion  of  elytron  of  beetle,  greatly  enlarged.     (After  Riley.) 


2  CONNECTICUT   AGRICULTURAL   STATION,   BULL.    121. 


CONTENTS. 

Notice  as  to  Station  Bulletins  and  Reports,              -            ...  2 

Elm  Leaf  Beetle,       ..--..            .            .  3 

Transformation  and  Habits,       -            .            -             -             -            -  3 

Methods  of  Extermination — Use  of  Paris  Green,           -             .            -  3 

San  Jos^  Scale,          ........  q 

Occurrence  in  Connecticut  of  the  San  Jose  Scale  Insect,           -            -  6 

General  Appearance  of  the  Scale,          -            -            ...  g 

Effects  of  the  Scale  Insect  on  Fruit  Trees,        -            -            -            -  9 

Plants  subject  to  Attack,           -            -         '   -            -            -            -  10 

Origin  and  Spread,         ---....  10 

Life  History,      -            -            -            -            -            -            -            -  11 

Remedies,           ........  12 

Kerosene  Emulsion,  Rosin  "Wash,          -            -            -            -            -  13 

Trade  Values,            -            -            -            -            -            -            -            -  1 5 

Officers  and  Staff  for  1895,  .  .  .  .  .  .16 


Bulletins. 

The  Bulletins  of  this  Station  are  mailed  free  to  citizens  of  Con- 
necticut and  to  others  who  apply  for  them,  until  the  editions  are 
exhausted. 

Applications  should  be  renewed  annually  before  January  1st. 

The  matter  of  all  the  Bulletins  of  this  Station,  in  so  far  as  it  is 
new  and  of  permanent  value,  is  made  a  part  of  the  Annual 
Reports. 

I^^All  Bulletins  earlier  than  No.  71  and  also  Nos.  83,  93,  100, 
101,  102,  106  and  118,  are  exhausted  and  cannot  be  supplied. 

Station  Reports. 

The  Annual  Reports  of  this  Station,  printed  at  State  expense, 
are  by  law  limited  to  editions  of  12,000  copies,  of  which  5,000 
copies  are  bound  with  the  Annual  Reports  of  the  Connecticut 
State  Board  of  Agriculture,  and  distributed  by  the  Secretary  of 
the  Board,  T.  S.  Gold. 

After  exchanging  with  other  Experiment  Stations  and  Agricul- 
tural Journals,  the  reports  remaining  at  the  disjjosal  of  the  Sta- 
tion will  be  sent  to  citizens  of  Connecticut  who  shall  seasonably 
apply  for  them,  and  to  others  as  long  as  the  supply  lasts. 

JU^^The  Station  has  no  supply  of  its  Annual  Reports  for  the 
years  1877,  1878,  1879,  1880,  1881,  1883,  1887,  1891,  and  1893, 
but  some  of  them  may  be  obtained  from  Secretary  T.  S.  Gold,  of 
West  Cornwall,  Conn.,  at  the  cost  of  postage. 


THE   ELM   LEAF   BEETLE. 


THE   ELM-LEAF   BEETLE   {Galeruca  xanthomelmna). 

Numerous  inquiries  have  reached  us  lately  regarding  this  insect, 
which  is  proving  destructive  to  elm  trees  in  many  parts  of  the 
State.  The  beetle  (see  c,  k,  in  cut  on  title  page)  deposits  its  eggs, 
a,  e,  in  small  clusters  on  the  lower  side  of  the  young  leaves  early  in 
June,  the  larvae  hatch  out  in  about  a  week  and  at  once  begin 
feeding  upon  the  leaves.  These  larvae,  h,  g,  are  small  worms  about 
five-eighths  of  an  inch  long,  marked  on  each  side  with  a  broad 
blackish  stripe.  They  are  soft,  moist,  and  somewhat  hairy  to  the 
touch.  It  is  at  this  stage  that  the  insect  is  most  destructive,  eat- 
ing off  the  delicate  surface-tissue  of  the  leaves,  and  causing  the 
latter  to  become  shrivelled  and  brown,  and  eventually  to  fall 
from  the  tree.  By  the  end  of  June  or  early  in  July  the  worms 
become  full  grown.  They  then  crawl  down  or  fall  from  the  trees, 
and  in  crevices  of  the  bark  or  soil  or  under  grass  and  leaves  change 
to  soft,  yellowish  pupse,  j.  Ten  days  later  the  pupa  give  rise  to  the 
adult  insects,  small  yellowish  beetles,  c,  Jc,  about  one-quarter  of  an 
inch  in  length,  marked  on  the  back  with  two  black  stripes.  The 
beetles  ascend  the  tree  and  for  a  month  feed  upon  the  remaining 
leaves,  though  the  injury  done  by  them  is  much  less  than  that  due 
to  the  worms.  During  August  and  the  early  part  of  September  the 
beetles  enter  cracks  or  crevices,  where  they  secure  protection  dur- 
ing the  winter,  and  hibernate  until  late  in  May,  when  they  appear 
upon  the  young  leaves  to  deposit  their  eggs.*  It  seems  probable 
that  in  New  England  there  is  but  one  brood  during  the  season. 

Methods  of  Extermination. — This  insect  can  best  be  destroyed  in 
the  larval  and  pupal  conditions.  The  larvae  (worms)  are  found  in 
June  and  July  upon  the  leaves,  the  pupse  in  July  upon  the  trunks  of 
the  trees  and  on,  or  in,  the  ground  beneath  the  trees.  To  destroy  the 
worms  the  best  means  is  a  spray  of  water  mixed  with  Paris  greenf 
and  fresh  slacked  lime,  in  the  proportions  of  one  pound  of  Paris 
green  and  three  pounds  of  lime  to  one  hundred  and  fifty  gallons 
of  water.  The  lime  should  be  newly  slacked  and  strained  free 
from  grit  or  lumps. 

*  For  fuller  information  as  regards  the  life-history  of  this  pest,  we  refer  to  the 
recently  published  Bulletin,  No.  14,  of  the  Storrs  Agricultural  Experiment  Station, 
Storrs,  Conn.,  Prof.  W.  0.  Atwater,  Director. 

f  This  dangerous  substance,  containing  arsenic  and  copper,  requires  caution  in 
its  handling,  but  may  be  used  without  injury  if  not  swallowed  nor  introduced  into 
wounds. 


4  CONNECTICUT   AGRICULTURAL   STATION,    BULL.    121. 

To  reach  the  tops  of  high  trees  a  powerful  force  pump  and  a 
long  hose  are  necessary.  The  Douglas  Palmetto  spraying  pump, 
manufactured  by  W.  &  B.  Douglas,  Middletown,  Conn.,  is  well 
adapted  to  this  purpose  when  man-power  is  employed.  It  should 
be  mounted  upon  a  cask  and  raised  as  high  as  possible  above  the 
ground.  The  discharge  pipe  should  be  a  half-inch  rubber  hose, 
supported  on  a  light  pole,  so  that  the  spray  can  be  directed  well 
up  into  the  trees.     The  best  nozzle  to  use  is  the  McGowan. 

While  a  few  trees  may  be  cared  for  by  the  use  of  a  hand-pump, 
the  elms  in  a  city  like  New  Haven  require  much  more  powerful 
appliances. 

Last  year  Mr.  Stephen  Hoyt  of  New  Canaan,  Conn.,  had  a 
steam  spraying  outfit*  constructed,  by  the  use  of  which  the  trees 
upon  the  estate  of  Stephen  Hoyt's  Sons  have  been  treated  for  two 
seasons  with  success. 

From  their  experience,  kindly  communicated  and  illustrated 
to  us  in  all  details,  we  are  enabled  to  present  the  following  plan 
of  treatment  by  power,  adapted  for  use  on  a  large  scale. 

A  portable  steam  engine  of  eight,  ten,  or  more  horse-power 
with  a  double-acting  force  pump  and  a  tank  of  250  or  more  gal- 
lons capacity,  are  mounted  on  a  stout  wagon  with  a  platform  large 
enough  to  accommodate  the  engineer. 

The  force-pump  should  be  supplied  with  an  indicator  to  show 
the  water-pressure,  and  a  number  of  outlets,  four,  six,  or  eight, 
to  connect  with  as  many  lines  of  hose  as  may  be  practicable. 
Suitable  hose,  guaranteed  to  stand  200  lbs.  pressure  to  the  inch 
and  costing  12  cents  per  foot,  may  be  got  of  the  Mineralized  Rub- 
ber Co.,  18  Cliff  St.,  N.  Y.  The  Lightning  Hose  Coupling  is 
recommended. 

To  each  hose  is  attached  a  nozzle  adapted  for  producing  a  fine 
spray.  The  best  nozzle  for  use  with  power  is  the  McGowan, 
made  by  J.  J.  McGowan,  Ithaca,  N.  Y.,  costing  $1.10.  This  with 
180  lbs.  steam  pressure  throws  a  shower  of  fine  spray  vertically 
for  thirty  feet  or  more. 

The  tank,  to  be  charged  with  the  poison  drench,  should  be 
provided  with  an  agitator  to  keep  the  materials  in  the  tank  uni- 
formly mixed. 

Besides  the  horses  needful  to  bring  the  apparatus  into  position, 
a  driver  who  can  operate  the  agitator,  an  engineer,  four,  six,  or 

*  With  6  horse-power  engine,  250  gallon  tanli,  and  pump  operating  2  lines  of 
hose,  each  100  feet  long. 


THE    ELM    LEAF   BEETLE.  5 

possibly  eight  men  to  manage  as  many  lines  of  hose,  and  an 
assistant  to  charge  the  tank,  are  the  needful  force, 

A  man  with  creepers  ascends  a  tree,  carrying  a  stout  cord,  and 
choosing  a  good  position  in  a  crotch,  hauls  up  a  line  of  hose  and 
fastens  it  to  a  limb,  so  that  holding  the  hose  near  the  end  he  can 
direct  the  nozzle  on  all  sides.  The  power  being  applied,  the 
water,  with  the  poison  in  suspension,  is  forced  out  of  the  hose  in 
a  shower  of  fine  spray  which,  by  skillful  handling  of  the  nozzle,  is 
quickly  applied  to  all  parts  of  the  foliage.  To  avoid  waste  of 
liquid  the  spray  is  thrown  for  a  moment  only  on  any  one  point, 
one,  two  or  three  minutes  at  the  most  suflicing  to  finish  work  on 
large  trees. 

While  two  or  more  men  are  directing  the  spray  into  as  many 
trees,  the  same  number  are  climbing  the  adjacent  trees,  so  that 
the  engine  and  its  attendants  are  fully  occupied. 

Two  treatments  are  advisable,  the  first  in  May  as  soon  as  the 
leaves  are  half  grown,  in  order  to  destroy  the  beetles  before  they 
deposit  their  eggs ;  the  second  in  June  or  as  soon  as  it  is  seen 
that  the  eggs  which  have  been  laid  are  hatching  out.  This  is 
undoubtedly  the  most  effective  method  of  combatting  the  insect, 
and  should  be  kept  up  for  several  years. 

Trees  which,  like  many  in  New  Haven  and  elsewhere  at 
this  writing  (July  16),  have  lost  one-half  or  more  of  their  sound 
leaf- surface  may  be  expected  to  survive  the  present  attack,  but 
to  be  destroyed  beyond  remedy  by  the  myriads  of  beetles  and 
worms  that  will  appear  next  year,  unless  a  well  organized  cam- 
paign for  their  suppression  is  undertaken  early  next  spring. 

If,  for  any  reason,  the  spraying  of  the  trees  is  impracticable, 
efforts  must  be  made  to  destroy  the  insects  in  the  pupal  condition 
on  or  beneath  the  trees.  This  is  best  done  by  the  use  of  kerosene 
emulsion,  which  is  made  as  follows  :  Dissolve  one-half  pound  of 
common  hard  soap  in  one  gallon  of  boiling  water;  to  this  soap 
solution,  while  still  warm,  add  two  gallons  of  kerosene,  and  churn 
violently  for  five  minutes  until  a  creamy  emulsion  results,  p.  13. 
Dilute  this  by  stirring  with  ten  times  its  bulk  of  cold  water, 
and  sprinkle  it  freely  over  the  ground  through  a  watering-pot. 
The  application,  which  is  not  injurious  to  grass,  should  be  made 
in  such  a  quantity  as  to  saturate  the  soil  where  the  pupse  exist. 
By  carefully  examining  the  ground,  grass,  fallen  leaves,  etc., 
beneath  the  trees,  the  pupae  can  be  found,  and  the  proper  time  for 
applying  the  emulsion  as  well  as  the  extent  of  ground  demanding 


6  CONNECTICUT  AGRICULTURAL  STATION,  BULL.  121. 

treatment  can  be  ascertained.  In  this  climate  the  soft,  yellow 
pupoe  will  be  found  on  the  ground  from  the  middle  of  June  to  the 
middle  of  July  or  later,  according  to  the  season.  The  emulsion 
should  be  applied  as  soon  as  they  are  observed  and  the  application 
repeated  if  needful  to  destroy  them.  To  be  thoroughly  effective 
this  method  of  destroying  the  pnpse  must  be  practiced  each  year,* 

It  is  well  to  scrape  away  the  rough  outer  bark  of  the  trees  for 
some  distance  above  the  ground,  as  many  pupfe  are  likely  to  be 
concealed  in  the  crevices.  The  scrapings  evidently  should  be 
burned  or  drenched  with  kerosene. 

Very  many  descending  worms  are  easily  intercepted  by  a  band 
of  hay  an  inch  thick  and  8  inches  wide,  secured  to  the  scraped 
trunk  at  convenient  height  from  the  ground,  by  aid  of  a  6  in. 
girth  of  cheap  cotton  cloth,  which  is  first  tacked  by  one  end  to 
the  bark  and  after  j^acking  the  hay  under  it  around  the  tree,  is 
fastened  at  the  other  end  by  pins. 

As  often  as  the  hay  gets  stocked  with  worms  and  pupse,  the 
band  (but  not  the  naked  bark)  is  hammered  with  a  mallet  to 
crush  most  of  the  vermin. 

Thereupon  the  hay  with  any  live  insects  is  burned  and  replaced 
by  a  new  band. 


THE   SAN   JOS:fi   SCALE. 
By  Wm.  C.  Sturgis  and  W.  E.  BEixroisr. 

Occurrence  in  Connecticut. — The  appearance  of  the  San  Jose 
scale  (Asjndiotus  perniciosus)  is  an  event  of  very  great  import- 
ance to  all  our  fruit  growers.  The  objects  of  this  paper  are  to 
call  attention  to  this  dreaded  pest,  to  enable  the  reader  to  recog- 
nize the  scale,  and  to  indicate  remedies  that  will  check  its  further 
spread. 

During  a  visit  to  the  orchard  of  Mr.  Joseph  L.  Raub  of  New 
London,  on  June  12th,  we  were  struck  by  the  appearance  of  cer- 
tain young  peach  trees  which  were  then  apparently  dead,  though 
earlier  in  the  season  they  had  put  out  a  few  leaves  near  the  tips, 
and  last  year  had  been  exceptionally  vigorous.  Close  inspection 
showed  that  in  every  case  the  trunk  and  larger  limbs  were  fairly 

*  While  the  touch  of  very  little  kerosene  to  the  bodies  of  larvse  and  young 
pupse  is  fatal,  the  emulsion  may  fail  to  destroy  hairy  worms  or  older  pupse, 
because  the  hairs  of  the  former  or  the  "chitinous"  membranes  of  the  latter 
shield  the  soft  and  vulnerable  parts  from  actual  contact  with  it. 


THE  SAN  JOSE  SCALE.  7 

incrusted  with  a  grayish  coating  composed  of  vast  numbers  of 
scale  insects.  These  so  resembled  the  published  drawings  of  the 
San  Jose  scale,  Fig.  1,  page  8,  that  they  were  suspected  to  be  that 
pest.  Specimens  were  at  once  submitted  to  the  experienced  ento- 
mologists, Messrs.  L.  O.  Howard  of  the  U.  S.  Department  of  Agri- 
culture and  M.  V.  Slingerland  of  Cornell  University,  who  kindly 
examined  them  and  confirmed  our  conclusion.  The  specimens 
secured  on  June  12th  were  small  and  undeveloped,  having  appar- 
ently died  while  still  in  the  hibernating  condition.  On  June  20th, 
careful  notes  were  taken  of  the  condition  and  surroundings  of  the 
orchard,  which  occupies  an  isolated  position  on  the  outskirts  of 
the  city,  with  no  other  orchard  in  its  vicinity,  and  which  contains  a 
variety  of  fruit  trees  from  one  to  four  years  of  age.  It  was  evi- 
dent that  the  scale  had  not  come  from  the  neighborhood,  but  it 
was  still  more  evident  that  the  orchard  in  its  present  condition 
might  be  a  fertile  source  of  infection,  for  living  scales  were  found 
upon  fully  one-half  of  the  trees.  All  the  ti'ees  came  originally 
from  a  firm  in  New  Jersey,  and  were  set  out  in  or  since  1891. 
The  plantings  of  1891  and  1892  were  very  badly  affected,  many 
of  the  trees  being  completely  dead  and  covered  with  the  scale, 
others  being  killed  to  the  ground  but  sending  up  new  shoots  from 
the  roots.  Living  scales  were  found  principally  upon  the  trees 
set  out  in  1893,  but  the  insect  had  not  yet  completely  infested 
the  trees,  which  remained  comparatively  vigorous.  The  trees  set 
out  last  year  were  practically  free  from  scale.  From  these  facts 
it  is  evident  that  the  insect  was  introduced  upon  the  stock 
of  1891  and  1892  and  had  developed  until  the  trees  died; 
and  that  the  stock  of  1S93,  while  originally  infested  equally 
with  the  previous  jDlantings,  had  remained  sufficiently  vigor- 
ous to  show  but  little  evidence  of  the  attack.  Doubtless, 
however,  these  trees  offered  suitable  conditions  for  the  breeding 
of  the  pest  and  its  spread  to  the  still  unaffected  trees  of  the 
planting  of  1894.  The  freedom  from  scale  of  the  last  was 
undoubtedly  due  to  the  energetic  and  successful  measures  adopted 
in  1894  by  the  New  Jersey  firm  to  eradicate  the  scale  from  their 
nurseries  by  the  destruction  of  all  infected  trees,  and  the  fumiga- 
tion of  all  suspected  stock  befoi'e  placing  it  upon  the  market. 

Since  our  first  visit,  Mr.  Raub  has  undertaken  to  destroy  the 
trees  in  his  orchard  which  are  most  seriously  infested,  and  to 
apply  to  the  others  a  strong  solution  of  whale-oil  soap.  This 
will  undoubtedly  check  the  sj^read  of  the  scale  until  next  winter, 
when  more  drastic  remedies  can  be  applied  to  the  dormant  trees. 


8  CONNECTICUT  AGEICULTURAL  STATION,  BULL.  121. 

General  appearance  of  the  Scale. — When  the  scales  occur 
singly  they  are  not  easy  to  detect  with  the  naked  eye;  but  when, 
as  is  usually  the  case,  they  occur  in  groups,  they  are  easily  seen 
as  a  grayisli  and  roughened  or  pimply  coating  upon  the  bark, 
as  shown   in  Fig.   1.     This  coating,  when  scraped   ofi  with  the 


Fig.  1. — San  Jose  Scale:  Apple  Branch,  with  scales — natural  size. — (From  Insect 
Life.) 

thumb-nail  or  with  the  blade  of  a  knife,  appears  mingled  with  a 
yellowish  liquid  if  the  insects  composing  it  are  alive.  In  severe 
cases  the  bark  is  completely  covered  with  this  scaly  coating, 
and  upon  removing  the  bark  the  delicate  tissues  beneath  are 
seen  to  present  a  pinkish  or  purplish  color.  When  a  tree  is 
but  slightly  affected,  the  scales  ai-e  usually  found  singly  or  in 
small  groups  upon  the  twigs,  often  at  the  base  of  the  leaves. 
When  the  scales  occur  upon  the  fruit,  it  is  usually  in  the  form 
of  scattered  individuals  closely  attached  to  the  surface,  each 
one  being  surrounded  with  a  purplish  ring,  Fig.  2.  The 
separate  scales  measure,  when  fully  grown,  about  one-eighth 
of  an  inch  in  diameter,  are  almost  circular,  slightly  convex  with 
a  minute  blackish  projection  in  the  center,  and  are  of  a  dirty 
brown  or  gray  color.  The  scale  may  be  easily  lifted  upon  the 
point  of  a  pen-knife,  and  the  insect  beneath  it,  if  alive,  is  seen  as 
a  small  bit  of  yellowish  jelly.  This  scale  difiers  in  appearance 
from  other  scales  commonly  found  upon  fruit  trees ;  it  is  rounder 
than  the  "oyster-shell  bark  louse,"  and  is  smaller  and  darker  in 


THE  SAN  JOSE  SCALE. 


color  than  the  "scurfy  bark  louse."  In  fact  it  is  the  only  scale 
among  those  commonly  found  on  fruit  trees  in  Connecticut, 
which  is  distinctly  circular  in  outline. 


Fig.  2. — San  Jose  Scale :  a,    Pear,   moderately   infested — natural  size  :  6,  female 
scale — enlarged. — (From  Insect  Lije.) 

Effect  of  the  scale  on  the  trees. — The  pernicious  effects  of  the  San 
Jose  scale  are  in  a  great  measure  due  to  its  inconspicuous  char- 
acter, and  to  the  fact  that  its  eflfect  upon  the  vitality  of  the  tree 
is  not  at  once  apparent.  During  the  first  season  of  its  attack,  the 
tree  may  be  apparently  healthy,  with  full  leafage  and  abundant 
fruit.  As  the  scale  spreads,  however,  the  efiect  becomes  more 
plainly  visible,  though  it  is  such  as  might  readily  be  attributed  to 
the  attacks  of  borers  or  to  drought.  Only  the  most  careful 
observation  will  discover  the  true  cause  of  disturbance.  Gener- 
ally by  the  second  or  third  season  only  does  the  scale  become  so 
abundant  as  to  be  conspicuous,  and  by  that  time  the  whole  tree 
is  infested  with  the  grayish  coating  of  scales ;  in  its  weakened 


10        CONNECTICUT  AGRICULTURAL  STATION,  BULL.  121. 

condition  it  succumbs  easily  to  an  exceptionally  severe  winter, 
and  though  it  may  put  forth  leaves,  they  shortly  wither,  and 
before  the  cause  of  the  trouble  is  actually  known,  the  tree  is  prac- 
tically dead.  If  taken  in  time,  however,  it  is  not  difficult  to 
check  its  ravages,  and  we  would  therefore  urge  all  fruit-growers 
to  inspect  their  trees  with  care,  and  to  send  us  specimens  of  any 
insect  found  bearing  resemblance  to  this  scale. 

Plants  subject  to  the  attacks  of  the  scale. — The  San  Jose  scale 
has  been  thus  far  found  in  Connecticut  upon  the  Peach,  Apple, 
Pear,  Plum  and  Currant,  but  information  from  other  States  shows 
that  it  may  attack  most  of  our  large  and  small  fruits,  and  the  rose, 
hawthorn,  elm,  basswood,  alder,  sumach,  English  walnut  and 
various  evergreens. 

Origin  and  spread. — This  insect  was  formerly  supposed  to  have 
been  introduced  into  California  from  Chili,  in  the  year  1870,  but 
later  information  obtained  by  Mr.  L.  O.  Howard,  Chief  of  the 
Division  of  Entomology,  IT.  S.  Department  of  Agriculture,  seems 
to  show  that  the  Pacific  coast  was  probably  its  original  home, 
whence  it  spread  to  Chili  and  other  countries. 

It  was  first  noticed  by  fruit  shippers  near  San  Jose,  Santa  Clara 
County,  California.  No  exterminative  measures  were  taken  and 
a  few  years  later  the  Pacific  slope  was  largely  infested. 

Prof.  J.  H.  Comstock  first  described  it  in  the  report  of  the 
U.  S.  Department  of  Agriculture  for  1880,  He  found  it  doing 
much  damage  in  California  and  regarded  it  as  the  most  destruc- 
tive scale  insect  known. 

The  Atlantic  States,  however,  were  supposed  to  be  uninfested 
until  the  summer  of  1893,  when  it  appeared  upon  orchard  trees 
in  Charlottesville,  Va.  The  attention  of  Dr.  C.  V.  Riley,  then 
U.  S.  Entomologist,  was  called  to  the  fact  of  its  presence,  and 
measures  for  its  suppression  were  immediately  employed. 

It  was  soon  discovered  that  this  was  not  the  only  center  of 
infection,  but  that  the  scale  existed  at  De  Funiak  Spring,  Florida ; 
Bartle,  Indiana;  Neavitt  and  Chestertown,  Maryland;  Lewis- 
burg  and  Atglen,  Pennsylvania,  and  in  several  localities  in  New 
York  and  New  Jersey.  It  has  recently  been  found  in  Delaware 
and  on  Long  Island. 

The  introduction  of  the  San  Jose  scale  into  the  Eastern  States 
has  been  traced  to  the  importation  of  Japanese  plum  trees  into 
New  Jersey  from  California. 


THE  SAJSr  JOSE  SCALE, 


11 


Like  other  scale  insects,  the  San  Jose  scale  can  spread  only  a 
short  distance  each  year,  unless  its  distribution  is  aided  by  the 
agency  of  wind,  water,  or  animals. 

Probably  its  distribution  in  this  country  has  been  largely 
efiected  through  shipments  of  fruit  and  nursery  stock ;  but  the 
insect  has  been  found  upon  other  insects,  and  these,  especially  the 
flying  ones,  have  doubtless  assisted  in  its  dissemination. 

Life  History. — This  insect  is  viviparovxs;  i.  e.,  brings  forth 
living  young.  Fig,  3. 


Fig.  3. — San  Jose  Scale  insect:  c,  adult  female  containing  young — greatly 
enlarged:  d,  anal  fringe  of  same — still  more  enlarged. — (From  Insect 
Life) 

In  California  three  annual  broods  appear,  but  for  our  climate 
the  number  of  yearly  broods  has  not  been  definitely  determined. 

The  San  Jose  scale  survives  the  winter  either  in  the  q^^  or  in  a 
half  grown  state.  It  becomes  fully  developed  and  reproduces 
about  the  last  of  May  or  first  of  June,  and  successive  broods 
appear  until  winter  begins. 

The  newly  born  or  hatched  individuals,  Fig,  4,  unlike  their 
female  parent,  have  no  scaly  covering  but  crawl  about  like 
ordinary  plant  lice.  They  are  very  small  at  first.  The  period  of 
activity  lasts  but  a  day  or  two,  sometimes  only  a  few  hours, 
when  the  young  insects  settle  upon  the  bark  and  become  fixed.    . 


12         CONNECTICUT  AGRICULTURAL  STATION,  BULL.  121. 

The  scaly  covering  then  begins  to  form.  The  insect  soon  molts 
and  the  cast-off  skin  uniting  with  a  waxy  secretion  forms  the  visi- 
ble external  scale. 


'«;^=:l»^q[7^- 


Tig.  4. — San  Jose  Scale  insect:  a,  young  larva — greatly  enlarged:  h,   antenna  of 
same — still  more  enlarged. — (From  Insect  Life.) 

The  female  insect  cannot  change  lier  place  after  the  scaly  cov- 
ering begins  to  form,  but  the  male  is  able  to  emerge  from  his 
cover,  and  being  winged  can  travel  short  distances,  Fig.  5. 

Remedies. — As  soon  as  the  scale  is  discovered,  and  before  any 
wash  or  other  treatment  is  applied,  the  trees  should  be  cut  back 
as  severely  as  seems  advisable,  and  all  the  cuttings  burned,  as,  in 
the  case  of  newly  infected  stock,  most  of  the  scales  occur  on  the 
terminal  shoots. 

Gas  Treatment. — This  requires  an  oiled  canvas  or  some  other 
gas-tight  tent  in  which  the  tree  is  enveloped.  Hydrocyanic  acid 
gas  is  then  generated  by  pouring,  say  three  fluid  ounces  of  water 
into  an  earthen-ware  vessel,  adding  one  fluid  ounce  of  commercial 
sulphuric  acid  (oil  of  vitriol),  and  lastly  one  ounce  (by  weight)  of 
fused  potassium  cyanide,  these  materials  making  enough  gas  to 
fill  a  space  of  one  hundred  and  fifty  cubic  feet. 

If  this  treatment  is  employed^  the  greatest  caution  must  be  taken 
not  to  breathe  the  gas,  for  hydrocyanic  [or  prussic)  acid  is  a  most 
dangerous  poison. 


THE  SAN  JOSE  SCALE. 


13 


According  to  Lintner  (Ball.  N.  Y.  State  Mus.,  Vol.  3,  No.  13, 
p.  302)  Mr.  Howard  lately  reports  the  gas  treatment  as  not 
wholly  efficacious  in  Virginia,  possibly  owing  to  the  more  com- 
plete dormancy  of  the  insects  in  the  East  than  in  California,  where 
it  was  first  successfully  employed. 


Fig.  5. — San  Jose  Scale  insect:  male  adult — greatly  enlarged. — (From  Insect  Life.) 


Summer  washes. — Either  weak  rosin  wash  or  dilute  kerosene 
emulsion  is  advised  for  keeping  the  scale  in  check  during  the  Sum- 
mer. Neither  will  do  more  than  this,  since  the  young  hatch  out  at 
intervals  throughout  the  Summer,  and  this  treatment  will  not  kill 
the  mature  scales. 

The  following  formulas  are  recommended  : — 

Weak  Rosin  Wash. 

Eosin - - 20  pounds 

Caustic  soda - 5  pounds 

Fish-oil 2^    pints 

Water  to  make 100  gallons 

Pulverize  the  rosin  and  soda,  add  the  oil,  and  place  the  mixture  in  a  large 
kettle  with  water  sufficient  to  cover  it.  Boil  for  one  or  two  hours  with  occa- 
sional additions  of  water,  until  the  compound  will  mix  perfectly  with  water 
instead  of  breaking  up  into  yellowish  flakes.     Dilute  for  use  to  100  gallons. 

Standard  Kerosene  Emulsion. 

Kerosene - 2  gallons 

Common  soap  or  whale-oil  soap J^  pound 

Water 1    gallon 


14         CONNECTICUT  AGRICULTURAL  STATION,  BULL.  121, 

Heat  the  solution  of  soap  and  add  it  boiling  hot  to  the  kerosene  ;  chum 
the  mixture  by  means  of  a  force  pump  and  spray  nozzle  for  five  or  ten  min- 
utes. The  emulsion,  if  perfect,  forms  a  cream  which  thickens  upon  cooling, 
and  should  adhere  without  oiliness  to  the  surface  of  glass.  If  the  water  is 
hard,  add  a  little  lye  or  soda^  enough  to  make  it  feel  very  slightly  slippery. 

For  use,  dilute  with  nine  times  its  bulk  of  cold  water. 

Either  of  these  washes  should  be  applied  at  least  three  times 
during  the  Summer.  As  has  been  said,  these  washes  will  do  no 
more  than  prevent  the  serious  increase  of  the  insects  during  the 
Summer.  For  thoroughly  effective  treatment  we  must  rely  upon 
strong  washes  applied  in  the  Winter,  when  the  trees  are  not  liable 
to  injury. 

Winter  washes. — Mr.  Howard  recommends  the  following 
washes  for  Winter  use :  Two  pounds  of  Whale-oil  soap  dissolved 
in  one  gallon  of  water,  applied  thoroughly  as  a  spray,  or  by. 
means  of  a  brush.  He  records  this  treatment  as  "  fatal  to  all  the 
scales  on  the  trees  sprayed  with  it." 

Strong  Rosin  Wash. — A  rosin  wash  made  as  before  given  for 
the  Summer  rosin  wash,  but  diluted  to  only  16  gallons  and 
accordingly  of  six  times  the  strength,  is  recorded  by  Mr.  Howard 
as  "fatal  to  all  the  scales  on  the  trees  sprayed  with  it." 

Potash  Wash. — Dr.  Smith  recommends,  as  a  result  of  his  ex- 
periences in  New  Jersey,  a  wash  consisting  of  a  saturated  solu- 
tion of  crude  or  commercial  potash,  i.  e.,  potash  in  a  quantity  of 
water  just  sufficient  to  dissolve  it.  This  is  applied  with  a  cloth 
or  a  brush,  or  as  a  spray.  The  potash  serves  to  corrode  and 
loosen  the  scales,  killing  many  of  the  insects  beneath  them ;  and 
a  spray  of  kerosene  emulsion  a  month  later  completes  the  work 
of  destruction. 

On  the  whole,  the  Winter  treatment  with  whale-oil  soap,  or 
strong  rosin  wash,  seems  to  leave  nothing  to  be  desired,  while 
in  order  to  keep  the  insect  in  check  during  the  Summer,  or  until 
this  treatment  can  be  safely  applied,  either  of  the  two  Summer 
washes  described  above  will  prove  valuable. 

Winter  washes  should  be  applied  soon  after  the  leaves  fall,  as 
the  scales  are  thought  to  be  more  susceptible  to  treatment  at  that 
time  than  later  in  the  winter. 

Summer  washes  should  be  applied  at  least  three  times  at  inter- 
vals during  the  summer.  Frequent  rains  will  necessitate  re- 
peated applications. 


TRADE   VALUES    OF   FERTILIZERS.  15 

TRADE-YALUES    OF    FERTILIZER   INGREDIENTS   IN 
RAW  MATERIALS  AND  CHEMICALS,  FOR  1895. 

Correction. 

In  the  statement  printed  on  page  3  of  Bulletin  120,  the  trade 
values  of  water-soluble  and  of  citrate-soluble  phosphoric  acid  are 
erroneous.  Instead  of  6^  and  6  cents  per  pound  respectively, 
they  should  be  6  and  5^  cents  per  pound. 

The  full  schedule  for  the  valuation  of  fertilizers  in  1895  that 
has  been  adopted  by  the  Connecticut,  Massachusetts,  Rhode  Is- 
land and  New  Jersey  Stations  is  correctly  given  as  follows  : 

Cents 
per  lb. 

Nitrogen  in  ammonia  salts  (ammonic  nitrogen) 18-J- 

nitrates  (nitric  nitrogen) 15 

Organic  nitrogen  of  dry  and  fine  ground  fish,  meat  and  blood..   16^ 

of  cottonseed  meal 12 

of  fine  bone  and  tankage 16 

of  fine-medium  bone  and  tankage 14 

of  medium  bone  and  tankage 11 

of  coarse  bone  and  tankage.. 5 

of  hair,  horn  shavings  and  coarse  fish  scrap..     5 

Phosphoric  acid,  water-soluble 6 

citrate-soluble* _     5^ 

of  dry  fine  ground  fish,  bone  and  tankage 5^ 

of  fine-medium  bone  and  tankage 4J 

of  medium  bone  and  tankage 3 

of  coarse  bone  and  tankage 2 

of  cotton  seed  meal,  and  wood  ashes 5 

of  mixed  fertilizers,  insoluble  in  both   water 
and  ammonium  citrate 2 

Potash  as  high-grade  sulphate  and  in  forms  free  from  muriate 

(or  chlorides) 5^ 

as  muriate 4+ 

In  Mixed  Fertilizers,  organic  nitrogen  is  reckoned  at  16^  cents 
per  pound,  the  price  of  nitrogen  in  raw  materials  of  the  best 
quality;  insoluble  phosphoric  acid  is  reckoned  at  2  cents:  potash 
is  rated  at  4-|  cents,  if  sufficient  chlorine  be  present  in  the  fertilizer 
to  combine  with  it  to  make  muriate ;  if  there  is  more  potash 
present  than  will  combine  with  the  chlorine,  then  this  excess  of 
potash  is  reckoned  at  5:^  cents  per  pound. 

*  Dissolved  from  2  grams  of  the  unground  phosphate  previously  extracted  with 
pure  water,  by  100  c.  c.  neutral  solution  of  ammonium  citrate,  sp.  gr.  1.09,  in  30 
minutes,  at  65°  C,  with  agitation  once  in  five  minutes.  Commonly  called 
"reverted  "  or  "backgone  "  Phosphoric  Acid. 


COHNECTICOT   A&RICULTORAL  EIPERIMENT   STATION. 

OFFICERS   AND   STAFF   FOR   1895. 


STATE    BOARD   OF   CONTROL. 

Ex-officio, 
His  Excellency  VINCENT  0.  COFFIN,  President. 

Term 
Appointed  by  Connecticut  State  Agricultural  Society :  expires, 

Hon.  E,  H.  HYDE,  Stafford,  Vice-President.  July  1,  1897 

Appointed  by  Board  of  Trustees  of  Wesleyan  University : 
Prof.  W.  O.  ATWATER,  Middletown.  1897 

Appointed  by  Governor  and  Senate : 
EDWIN  HOYT,  New  Canaan.  1898 

JAMES  H.  WEBB,  Hamden.  1896 

Appointed  by  Board  of  Agriculture : 
T.  S.  GOLD,  West  Cornwall.  1898 

Appoi7ited  by  Governing  Board  of  Sheffield  Scientific  School : 
W.  H.  BREWER,  New  Haven,  Secretary  and  Treasurer.  1896 

'«#  ^: 

^  Ex-officio. 

S.  W.  JOHNSON,  New  Haven,  Director. 


s 


Station  Staff. 
Chejnists. 
S.  W.  JOHNSON,  Director.  T.  B.  OSBORNE,  Ph.D. 

E.  H.  JENKINS,  Ph.D.,  Vice-Dir.  A.  W.  OGDEN,  Ph.B. 

A.  L.  WINTON,  Ph.B.  G.  F.  CAMPBELL,  Ph.B. 

Mycologist. 
WILLIAM  C.  STURGIS,  Ph.D. 

Horticulturist. 
W.  E.  BRITTON,  B.S. 

Grass  Gardener. 
JAMES  B.  OLCOTT,  South  Manchester. 

Stenographer  and  Clerk. 
Miss  C.  S.  GREEN. 

In  charge  of  Buildings  and  Grounds. 
CHARLES  J.  RICE. 

Laboratory  Helpers. 
HUGO  LANGE.  JULIUS  KORN. 

Sampling  Agents. 
C.  L.  BACKUS,  Andover.  M.  H.  PARKER,  So.  Coventry. 


University  of 
Connecticut 

Libraries 


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